Low Ligation of Inferior Mesenteric Artery in Laparoscopic Anterior Resection for Rectal Cancer Reduces Genitourinary Dysfunction: Results From a Randomized Controlled Trial (HIGHLOW Trial)

Low ligation of the inferior mesenteric artery in robotic mid-low rectal cancer surgery: a comparative study from a single-center

Laparoscopic total mesorectal excision is the main surgical approach for treating rectal cancer, but there is still no clear consensus on the issue of low ligation of the inferior mesenteric artery during the procedure. Robotic surgery has been shown to have certain advantages over laparoscopic surgery in multiple studies, but further research is needed to better understand the outcomes of robotic surgery in the context of low ligation procedures. In this study, we included 1590 patients with mid-low rectal cancer. Among them, 942 patients underwent low ligation surgery (LL), divided into 138 in the robotic group and 804 in the laparoscopic group. The high ligation surgery (HL) group consisted of 648 patients. The results of LL vs HL showed that the LL group had faster bowel movement recovery (P = 0.003), lower anastomotic leak rate (P = 0.032), and lower International Prostate Symptom Score (IPSS) at 6 months postoperatively (P < 0.001). The results of Rob-LL vs Lap-LL showed that the Rob-LL group had longer operative time (P < 0.001), less blood loss (P = 0.001), more lymph nodes retrieved (P = 0.045), and lower Wexner score at 2 weeks postoperatively (P = 0.029). The concept of low ligation of the inferior mesenteric artery is a promising surgical approach that can accelerate the patient's functional recovery. When combined with robotic technology, it may offer more benefits than laparoscopic techniques.

A novel technique for NO.253 lymph node dissection and left colic artery preservation to avoid potential postoperative internal hernia in laparoscopic radical resection for rectal cancer

BACKGROUND

The preservation of the left colic artery (LCA) has emerged as a preferred approach in laparoscopic radical resection for rectal cancer. However, preserving the LCA while simultaneously dissecting the NO.253 lymph node can create a mesenteric defect between the inferior mesenteric artery (IMA), the LCA, and the inferior mesenteric vein (IMV). This defect could act as a potential "hernia ring," increasing the risk of developing an internal hernia after surgery. The objective of this study was to introduce a novel technique designed to mitigate the risk of internal hernia by filling mesenteric defects with autologous tissue.

METHODS

This new technique was performed on eighteen patients with rectal cancer between January 2022 and June 2022. First of all, dissected the lymphatic fatty tissue on the main trunk of IMA from its origin until the LCA and sigmoid artery (SA) or superior rectal artery (SRA) were exposed and then NO.253 lymph node was dissected between the IMA, LCA and IMV. Next, the SRA or SRA and IMV were sequentially ligated and cut off at an appropriate location away from the "hernia ring" to preserve the connective tissue between the "hernia ring" and retroperitoneum. Finally, after mobilization of distal sigmoid, on the lateral side of IMV, the descending colon was mobilized cephalad. Patients'preoperative baseline characteristics and intraoperative, postoperative complications were examined.

RESULTS

All patients' potential "hernia rings" were closed successfully with our new technique. The median operative time was 195 min, and the median intraoperative blood loss was 55 ml (interquartile range 30-90). The total harvested lymph nodes was 13.0(range12-19). The median times to first flatus and liquid diet intake were both 3.0 days. The median number of postoperative hospital days was 8.0 days. One patient had an injury to marginal arterial arch, and after mobolization of splenic region, tension-free anastomosis was achieved. No other severe postoperative complications such as abdominal infection, anastomotic leakage, or bleeding were observed.

CONCLUSIONS

This technique is both safe and effective for filling the mesenteric defect, potentially reducing the risk of internal hernia following laparoscopic NO.253 lymph node dissection and preservation of the left colic artery in rectal cancer surgeries.

Investigation of postoperative erectile dysfunction in colorectal surgery patients and comparison of results

BACKGROUND

Although surgical treatment is curative for colorectal cancers, erectile dysfunction (ED) is one of the complications that affect the patient quality of life. The present study aimed to evaluate sexual dysfunction in patients who underwent anterior resection (AR) and low AR (LAR) surgery secondary to rectosigmoid pathologies in our clinic, to analyze the effective variables, and to compare the results.

METHODS

In the retrospectively designed study, male patients who underwent surgery for malignancy or other surgical pathologies in the General Surgery Clinic between January 2017 and December 2022 were examined. Female gender, patients under 18 years of age, and patients who refused to participate in the study were excluded.

RESULTS

The high age of the patient increased the risk of severe ED in the postoperative period. However, surgical technique, alcohol use, American Society of Anesthesiologists (ASA) score, and Clavien-Dindo class were not determinants in the presence of severe ED.

CONCLUSION

ED is an emerging medical problem that affects patients who undergo colorectal surgery adversely both in social and psychological aspects. Discussions on the issue are still ongoing. Clinicians' concerns can be addressed in the future as the number of prospectively designed studies involving more homogeneous and larger populations increases.

A nomogram for predicting lymph nodes metastasis at the inferior mesenteric artery in rectal cancer: a retrospective case-control study

According to past and current literature, metastasis of the lymph nodes at the inferior mesenteric artery (IMA-LN), also known as 253LN of colorectal cancer has been seldom investigated. To date, there are still controversies on whether the 253LN need to be routinely cleaned. Using specific criteria, 347 patients who underwent radical resection for rectal cancer between April 2019 and July 2022 were selected for the study. Logistic regression was used to determine the likelihood that a patient may suffer 253LN metastasis, and a nomogram for 253LN metastasis subsequently developed. The c-index and calibration curve were used to evaluate precision and discrimination in the nomogram, and the appropriateness of the final nomogram for the clinical setting determined using decision curve analysis (DCA). 253LN metastases appeared in the pathological specimens of 29 (8.4%) of the selected patients. Logistic regression showed that preoperative parameters including serum carcinoembryonic antigen (CEA) value ( > 5 ng / ml, OR = 2.894, P = 0.023), distance from anal margin (> 9 cm, OR = 2.406, P = 0.045) and degree of differentiation (poor, OR = 9.712, P < 0.001) were significantly associated with 253LN metastasis. A nomogram to predict 253LN metastasis in rectal cancer was developed and showed considerable discrimination and good precision (c-index = 0.750). Furthermore, DCA confirmed that the nomogram has some feasibility for the clinical environment. Clinicopathological and radiological patient data can be pivotal for making surgical decisions relating to 253LN metastasis. A nomogram was developed using this data, providing an objective method that can significantly improve prognoses in colorectal cancer.

The Atlas of the Inferior Mesenteric Artery and Vein under Maximum-Intensity Projection and Three-Dimensional Reconstruction View

(1) Background: Understanding vascular patterns is crucial for minimizing bleeding and operating time in colorectal surgeries. This study aimed to develop an anatomical atlas of the inferior mesenteric artery (IMA) and vein (IMV). (2) Methods: A total of 521 patients with left-sided colorectal cancer were included. IMA and IMV patterns were identified using maximum-intensity projection (MIP) and three-dimensional (3D) reconstruction techniques. The accuracy of these techniques was assessed by comparing them with surgical videos. We compared the amount of bleeding and operating time for IMA ligation across different IMA types. (3) Results: Most patients (45.7%) were classified as type I IMA, followed by type II (20.7%), type III (22.6%), and type IV (3.5%). Newly identified type V and type VI patterns were found in 6.5% and 1% of patients, respectively. Of the IMVs, 49.9% drained into the superior mesenteric vein (SMV), 38.4% drained into the splenic vein (SPV), 9.4% drained into the SMV-SPV junction, and only 2.3% drained into the first jejunal vein (J1V). Above the root of the left colic artery (LCA), 13.1% of IMVs had no branches, 50.1% had one, 30.1% had two, and 6.7% had three or more branches. Two patients had two main IMV branches, and ten had IMVs at the edge of the mesocolon with small branches. At the IMA root, 37.2% of LCAs overlapped with the IMV, with 34.0% being lateral, 16.9% distal, 8.7% medial, and both the marginal type of IMV and the persistent descending mesocolon (PDM) type represented 1.4%. MIP had an accuracy of 98.43%, and 3D reconstruction had an accuracy of 100%. Blood loss and operating time were significantly higher in the complex group compared to the simple group for IMA ligation (p < 0.001). (4) Conclusions: A comprehensive anatomical atlas of the IMA and IMV was provided. Complex IMA patterns were associated with increased bleeding and operating time.

Long-term clinical outcomes after high and low ligations with lymph node dissection around the root of the inferior mesenteric artery in patients with rectal cancer

PURPOSE

This study aimed to evaluate the long-term clinical outcomes based on the ligation level of the inferior mesenteric artery (IMA) in patients with rectal cancer.

METHODS

This was a retrospective analysis of a prospectively collected database that included all patients who underwent elective low anterior resection for rectal cancer between January 2013 and December 2019. The clinical outcomes included oncological outcomes, postoperative complications, and functional outcomes. The oncological outcomes included overall survival (OS) and relapse-free survival (RFS). The functional outcomes, including defecatory and urogenital functions, were analyzed using the Fecal Incontinence Severity Index, International Prostate Symptom Score, and International Index of Erectile Function questionnaires.

RESULTS

In total, 545 patients were included in the analysis. Of these, 244 patients underwent high ligation (HL), whereas 301 underwent low ligation (LL). The tumor size was larger in the HL group than in the LL group. The number of harvested lymph nodes (LNs) was higher in the HL group than in the LL group. There were no significant differences in complication rates and recurrence patterns between the groups. There were no significant differences in 5-year RFS and OS between the groups. Cox regression analysis revealed that the ligation level (HL vs. LL) was not a significant risk factor for oncological outcomes. Regarding functional outcomes, the LL group showed a significant recovery in defecatory function 1 year postoperatively compared with the HL group.

CONCLUSION

LL with LNs dissection around the root of the IMA might not affect the oncologic outcomes comparing to HL; however, it has minimal benefit for defecatory function.

Inferior Mesenteric Artery Ligation Level in Rectal Cancer Surgery beyond Conventions: A Review

Within the intricate field of rectal cancer surgery, the contentious debate over the optimal level of ligation of the inferior mesenteric artery (IMA) persists as an ongoing discussion, influencing surgical approaches and patient outcomes. This narrative review incorporates historical perspectives, technical considerations, and functional as well as oncological outcomes, addressing key questions related to anastomotic leakage risks, genitourinary function, and oncological concerns, providing a more critical understanding of the well-known inconclusive evidence. Beyond the dichotomy of high versus low tie, it navigates the complexities of colorectal cancer surgery with a fresh perspective, posing a transformative question: "Is low tie ligation truly reproducible?" Considering a multidimensional approach that enhances patient outcomes by integrating the surgeon, patient, technique, and technology, instead of a rigid and categorical statement, we argued that a balanced response to this challenging question may require compromise.

Preservation of the inferior mesenteric artery VS ligation of the inferior mesenteric artery in left colectomy: evaluation of functional outcomes-a prospective non-randomized controlled trial

Vascular approach during elective laparoscopic left colectomy impacts post-operative outcomes. The aim of our study was to evaluate how different approaches impact positively defecatory, urinary and sexual functions and quality of life during elective laparoscopic left colectomy. A prospective non-randomized controlled trial at two tertiary center was conducted. All patients who underwent elective laparoscopic left colonic resection from January 2019 to July 2022 were analyzed. They were divided into two groups based on Inferior Mesenteric Artery (IMA) preservation with distal ligation of sigmoid branches close to a colonic wall for complicated diverticular disease and IMA high tie ligation for oncological disease. Patients were asked to fulfil standardized, validated questionnaires to evaluate pre and post-operative defecatory, urinary and sexual functions and quality of life. Defecatory disorders were assessed by high-resolution anorectal manometry preoperatively and six months after surgery. A total of 122 patients were included in the study. The 62 patients with IMA preservation showed a lower incidence of defecatory disorders also confirmed by manometer data, minor incontinence and less lifestyle alteration than the 60 patients with IMA high tie ligation. No urinary disorders such as incomplete emptying, frequency, intermittence or urgency were highlighted after surgery in the IMA preservation group. Evidence of any sexual disorders remained controversial. The IMA-preserving vascular approach seems to be an effective strategy to prevent postoperative functional disorders. It is a safe and feasible technique especially for diverticular disease. New prospective randomized and highly probative studies are needed to confirm the effectiveness in specific clinical situations.

Level of Inferior Mesenteric Artery Ligation in Sigmoid Colon and Rectal Cancer Surgery: Analysis of Apical Lymph Node Metastasis and Recurrence

INTRODUCTION

Whether high or low ligation of the inferior mesenteric artery (IMA) is optimal for treating sigmoid colon and rectal cancers is controversial. The present study aimed to compare outcomes of high and low ligation of the IMA and determine the adequate extent of IMA lymph node dissection.

METHODS

Subjects were 455 consecutive stage I-III colorectal cancer patients who underwent curative surgery between 2011 and 2019. We assessed the association between the level of IMA ligation and overall survival and recurrence-free survival (RFS) by propensity score matching analysis. Clinicopathological features of IMA lymph node metastasis and recurrence patterns were analyzed.

RESULTS

After propensity score matching, the low ligation group had a significantly worse prognosis than that of the high ligation group for RFS (p = 0.039). Positive IMA lymph nodes were associated with pathological T3 or T4 stage and N2 stage. IMA lymph node recurrences in the high ligation group occurred at the superior left side of the IMA root. In contrast, all recurrences in the low ligation group occurred at the left colic artery bifurcation.

CONCLUSION

High ligation of IMA is oncologically safe. However, even with high ligation, care must be taken to ensure adequate lymph node dissection.

Impact on defecatory, urinary and sexual function after high-tie sigmoidectomy: a post-hoc analysis of a multicenter randomized controlled trial comparing extended versus standard complete mesocolon excision

OBJECTIVE

To assess the effect of high inferior mesenteric artery tie on defecatory, urinary, and sexual function after surgery for sigmoid colon cancer. Performing a sigmoidectomy poses a notable risk of causing injury to the preaortic sympathetic nerves during the high ligation of the inferior mesenteric artery, as well as to the superior hypogastric plexus during dissection at the level of the sacral promontory. Postoperative defecatory and genitourinary dysfunction after sigmoid colon resection are often underestimated and underreported.

METHODS

This study is a secondary research of a multicenter, single-blind, randomized clinical trial. The trial involved patients with sigmoid cancer who underwent either extended complete mesocolic excision (e-CME) or standard CME (s-CME). Patients completed questionnaires to assess defecatory, urinary, and sexual function before, 1 month after surgery, and 1 year after surgery. Multivariate analysis was conducted to identify factors associated with functional dysfunction.

RESULTS

Seventy-nine patients completed functional assessments before and 1 year after surgery. One year after sigmoidectomy with a high tie of the inferior mesenteric artery, 15.2% of patients had minor low anterior resection syndrome (LARS) and 12.7% had major LARS; 22.2% of males and 29.4% of females had urinary dysfunction; and 43.8% of males and 27.3% of females had sexual dysfunction. After multivariate analysis, no significant associations were found between clinical and surgical factors and gastrointestinal or urinary dysfunction after 1 year of surgery. Age was identified as the only factor linked to sexual dysfunction in both sexes (women, β =  - 0.54, p = 0.002; men β =  - 0.38, p = 0.010). Regarding recovery outcomes, diabetes mellitus was identified as a contributing factor to suboptimal gastrointestinal recovery (p = 0.033) and urinary recovery in women (p = 0.039). Furthermore, the treatment arm was found to be significantly associated with the recovery of erectile function after 1 year of surgery (p = 0.046).

CONCLUSIONS

A high tie of the inferior mesenteric artery during sigmoidectomy is associated with a high incidence of defecatory and genitourinary dysfunction. Age was identified as a significant factor associated with sexual dysfunction 1 year after sigmoid colon resection in both sexes.

TRIAL REGISTRATION

Clinical trials NCT03083951 HIGHLIGHTS: • One year after high-tie sigmoidectomy, 27.9% of patients had LARS; 22.2% of the men and 29.4% of the women had urinary dysfunction; and 43.8% of the men and 27.3% of the women had sexual dysfunction. • e-CME is associated with a high rate of urinary dysfunction in men 1 year after surgery. However, after multivariate analysis, no association was found between e-CME and urinary dysfunction in men. • Age was correlated with the recovery of sexual function in both sexes 1 year after surgery. Furthermore, diabetes mellitus was identified as the factor associated with poorer recovery of urinary function in females.

Inferior mesenteric artery ligation level in rectal cancer surgery: still no answer-a systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis is to summarize the current scientific evidence regarding the impact of the level of inferior mesenteric artery (IMA) ligation on post-operative and oncological outcomes in rectal cancer surgery.

METHODS

We conducted a systematic review of the literature up to 06 September 2022. Included were RCTs that compared patients who underwent high (HL) vs. anterior (LL) IMA ligation for resection of rectal cancer. The literature search was performed on Medline/PubMed, Scopus, and the Web of Science without any language restrictions. The primary endpoint was overall anastomotic leakage (AL). Secondary endpoints were oncological outcomes, intraoperative complications, urogenital functional outcomes, and length of hospital stay.

RESULTS

Eleven RCTs (1331 patients) were included. The overall rate of AL was lower in the LL group, but the difference was not statistically significant (RR 1.43, 95% CI 0.95 to 2.96). The overall number of harvested lymph nodes was higher in the LL group, but the difference was not statistically significant (MD 0.93, 95% CI - 2.21 to 0.34). The number of lymph nodes harvested was assessed in 256 patients, and all had a laparoscopic procedure. The number of lymph nodes was higher when LL was associated with lymphadenectomy of the vascular root than when IMA was ligated at its origin, but there the difference was not statistically significant (MD - 0.37, 95% CI - 1.00 to 0.26). Overall survival at 5 years was slightly better in the LL group, but the difference was not statistically significant (RR 0.98, 95% CI 0.93 to 1.05). Disease-free survival at 5 years was higher in the LL group, but the difference was not statistically significant (RR 0.97, 95% CI 0.89 to 1.04).

CONCLUSIONS

There is no evidence to support HL or LL according to results in terms of AL or oncologic outcome. Moreover, there is not enough evidence to determine the impact of the level of IMA ligation on functional outcomes. The level of IMA ligation should be chosen case by case based on expected functional and oncological outcomes.

Verification of blood flow path reconstruction mechanism in distal sigmoid colon and rectal cancer after high IMA ligation through preoperative and postoperative comparison by manual subtraction CTA

INTRODUCTION

We aimed to investigate manual subtraction computed tomography angiography (MS-CTA) to further confirm the distribution and classification of LCA (left colic artery) ascending/descending branches, then observe the postoperative blood flow path to illustrate how the above branches evolved to postoperative blood path.

MATERIAL AND METHODS

89 patients with distal sigmoid and rectal cancer were referred in our observation and underwent MS-CTA between June 2020 and March 2022. We classified the distribution of LCA and confirmed whether there exists AMCA (accessory middle colic artery). Then we planned blood flow path based on the classification of LCA branches before operation. High ligation was applied in regular radical surgery. During operation, we carefully protect the bifurcation of ascending and descending LCA. Then we compared the planned blood flow path with the actual postoperative blood flow path to verify the mechanism we proposed previously.

RESULTS

Of 89 patients, 82 cases met our criteria, we summarized 6 distribution pattens of LCA ascending and descending branches. These preoperative pattens are consistent with the inspection during operation. The postoperative blood flow path of 6 pattens is evolved from the above adjacent anastomotic branches and is consistent with the planned blood flow path. We also found 2 cases with IMA stenosis and 1 case with SMA stenosis under pathological condition, and their compensatory blood flow path is in accordance with our theory. The rate of the anastomotic leakage in our study group is relatively low (7.3%).

CONCLUSION

MS-CTA could confirm the distribution of LCA and AMCA, display accurate postoperative blood reconstruction path after IMA high ligation, and it further verified the mechanism we proposed previously, which is the proximal anastomotic branches forming new blood flow path from high-pressure area to the low-pressure area. This mechanism might be helpful for performing accurate laparoscopic sigmoid and rectal cancer surgery.

Computer-assisted rescue of the inferior mesenteric artery in a child with a giant ganglioneuroblastoma: A case report

BACKGROUND

Ganglioneuroblastoma (GNB) is a peripheral neuroblastoma (NB) with malignant degree between highly malignant NB and benign ganglioma (GN). Pathology is the gold standard of diagnosis. Although GNB is not uncommon in children, biopsy alone may lead to an inaccurate diagnosis, especially for giant tumors. However, surgical resection may be associated with significant complications. Here, we report a case of computer-assisted surgical resection of a giant GNB in a child and successful rescue of the inferior mesenteric artery.

CASE SUMMARY

A 4-year-old girl was admitted to our department for a giant retroperitoneal lesion, which was considered to be an NB by her local hospital. The symptoms of the girl disappeared spontaneously without treatment. On physical examination, a mass of about 10 cm × 7 cm could be palpated in her abdomen. Ultrasonography and contrast-enhanced computed tomography performed in our hospital also showed an NB, and there was a very thick blood vessel inside the tumor. However, aspiration biopsy revealed GN. Surgical resection is the best treatment option for this giant benign tumor. For precise preoperative evaluation, three-dimensional reconstruction was performed. It was clear that the tumor was close to the abdominal aorta. The superior mesenteric vein was pushed forward, and the inferior mesenteric artery passed through the tumor. Because GN generally does not invade blood vessels, we split the tumor with a CUSA knife during the operation and found that there was indeed a straight and intact vascular sheath. Arterial pulsation was observed in the completely exposed inferior mesenteric artery. The pathologists interpreting the tissue finally diagnosed it as a mixed GNB (GNBi), which is more malignant than GN. However, both GN and GNBi usually have a good prognosis.

CONCLUSION

This was a case of successful surgical resection of a giant GNB, and aspiration biopsy underestimated the pathological staging of the tumor. Preoperative three-dimensional reconstruction assisted with the radical resection of the tumor and rescue of the inferior mesenteric artery.

Deep-learning-based semantic segmentation of autonomic nerves from laparoscopic images of colorectal surgery: an experimental pilot study

BACKGROUND

The preservation of autonomic nerves is the most important factor in maintaining genitourinary function in colorectal surgery; however, these nerves are not clearly recognisable, and their identification is strongly affected by the surgical ability. Therefore, this study aimed to develop a deep learning model for the semantic segmentation of autonomic nerves during laparoscopic colorectal surgery and to experimentally verify the model through intraoperative use and pathological examination.

MATERIALS AND METHODS

The annotation data set comprised videos of laparoscopic colorectal surgery. The images of the hypogastric nerve (HGN) and superior hypogastric plexus (SHP) were manually annotated under a surgeon's supervision. The Dice coefficient was used to quantify the model performance after five-fold cross-validation. The model was used in actual surgeries to compare the recognition timing of the model with that of surgeons, and pathological examination was performed to confirm whether the samples labelled by the model from the colorectal branches of the HGN and SHP were nerves.

RESULTS

The data set comprised 12 978 video frames of the HGN from 245 videos and 5198 frames of the SHP from 44 videos. The mean (±SD) Dice coefficients of the HGN and SHP were 0.56 (±0.03) and 0.49 (±0.07), respectively. The proposed model was used in 12 surgeries, and it recognised the right HGN earlier than the surgeons did in 50.0% of the cases, the left HGN earlier in 41.7% of the cases and the SHP earlier in 50.0% of the cases. Pathological examination confirmed that all 11 samples were nerve tissue.

CONCLUSION

An approach for the deep-learning-based semantic segmentation of autonomic nerves was developed and experimentally validated. This model may facilitate intraoperative recognition during laparoscopic colorectal surgery.

The SAGES MASTERS program presents: the top 10 seminal articles for laparoscopic left and sigmoid colectomy pathway for uncomplicated disease

BACKGROUND

As one of the 8 Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Masters Program clinical pathways, the Colorectal Pathway aims to deliver educational content for the general surgeon organized along 3 levels of performance (competency, proficiency and mastery) each represented by an anchoring procedure. In this article, the SAGES Colorectal Task Force presents focused summaries of the top 10 seminal articles selected for laparoscopic left/sigmoid colectomy for uncomplicated disease.

METHODS

Using a systematic literature search of Web of Science, the most cited articles on laparoscopic left and sigmoid colectomy were identified, reviewed, and ranked by members of the SAGES Colorectal Task Force. Additional articles not identified in the literature search were included if deemed impactful by expert consensus. The top 10 ranked articles were then summarized, including their findings, strengths and limitations with emphasis on relevance and impact in the field.

RESULTS

The top 10 articles selected focus on variations in minimally invasive surgical techniques, video demonstrations, stratified approaches for benign and malignant disease as well as assessments of the learning curve.

CONCLUSIONS

The selected top 10 seminal articles for laparoscopic left and sigmoid colectomy in uncomplicated disease are considered by the SAGES colorectal task force to be fundamental to the knowledge base of minimally invasive surgeons as they progress to mastery in these procedures.

The SAGES MASTERS program presents: the top 10 seminal articles for laparoscopic left and sigmoid colectomy pathway for uncomplicated disease

BACKGROUND

As one of the 8 Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Masters Program clinical pathways, the Colorectal Pathway aims to deliver educational content for the general surgeon organized along 3 levels of performance (competency, proficiency and mastery) each represented by an anchoring procedure. In this article, the SAGES Colorectal Task Force presents focused summaries of the top 10 seminal articles selected for laparoscopic left/sigmoid colectomy for uncomplicated disease.

METHODS

Using a systematic literature search of Web of Science, the most cited articles on laparoscopic left and sigmoid colectomy were identified, reviewed, and ranked by members of the SAGES Colorectal Task Force. Additional articles not identified in the literature search were included if deemed impactful by expert consensus. The top 10 ranked articles were then summarized, including their findings, strengths and limitations with emphasis on relevance and impact in the field.

RESULTS

The top 10 articles selected focus on variations in minimally invasive surgical techniques, video demonstrations, stratified approaches for benign and malignant disease as well as assessments of the learning curve.

CONCLUSIONS

The selected top 10 seminal articles for laparoscopic left and sigmoid colectomy in uncomplicated disease are considered by the SAGES colorectal task force to be fundamental to the knowledge base of minimally invasive surgeons as they progress to mastery in these procedures.

International survey among surgeons on the perioperative management of rectal cancer

BACKGROUND

Several pivotal studies and international guidelines on the perioperative management of rectal cancer have been published. However, little is known about the current state of perioperative management of rectal cancer patients in clinical practice worldwide.

METHODS

An online survey including 13 questions focusing on key topics related to the perioperative management of patients with rectal cancer was conducted among colorectal surgeons registered within the database of the Research Institute Against Digestive Cancer (IRCAD).

RESULTS

A total of 535 respondents from 89 countries participated in the survey. Most surgeons worked in the European region (40.9%). Two hundred and fifty-four respondents (47.5%) performed less than 25% of surgical procedures laparoscopically. The most commonly used definition of the upper limit of the rectum was a fixed distance from the anal verge (23.4%). Magnetic resonance imaging was used to define the upper limit of the rectum by 258 respondents (48.2%). During total mesorectal excision (TME), 301 respondents (56.3%) used a high-tie technique. The most commonly constructed anastomosis was an end-to-end anastomosis (68.2%) with the majority of surgeons performing a leak test intraoperatively (88.9%). A total of 355 respondents (66.4%) constructed a diverting ostomy, and the majority of these surgeons constructed an enterostomy (82%). A total of 208 respondents (39.3%) closed a stoma within 8 weeks. Lastly, 135 respondents (25.2%) introduced a solid diet on postoperative day 1.

CONCLUSION

There is considerable heterogeneity in the perioperative management of rectal cancer patients worldwide with several discrepancies between current international practice and recommendations from international guidelines. To achieve worldwide standardization in rectal cancer care, further research is needed to elucidate the cause of this heterogeneity and find ways of improved implementation of best practice recommendations.

Potential short-term outcome advantage of low vs. high ligation of inferior mesenteric artery for sigmoid and rectal cancer: propensity score matching analysis

BACKGROUND

Whether to ligate the inferior mesenteric artery at its root during anterior resection for sigmoid colon or rectal cancer is still under debate. This study compared the surgical outcomes, postoperative recovery, and anastomotic leakage between high and low ligation of the inferior mesenteric artery through a subgroup analysis.

METHODS

This was a retrospective analysis of prospectively collected data. All patients who underwent colorectal resection for rectosigmoid cancer between December 2016 and December 2019 were enrolled. According to the surgical ligation level of the inferior mesenteric artery, the patients were categorized into either the high or low ligation group. The investigated population was matched using the propensity score method.

RESULTS

Overall, 894 patients with sigmoid or rectal cancer underwent elective anterior resection with high (577 patients) or low (317 patients) ligation of the inferior mesenteric artery. After the propensity score matching, 245 patients in each group were compared. High ligation of the inferior mesenteric artery was associated with higher incidence of anastomotic leakage (14.9% vs. 5.6%, P = 0.041) for mid- to low-rectum tumors and a higher incidence of complications (8.6% vs. 3.3%, P = 0.013) of grades 1-2 according to the Clavien-Dindo classification system.

CONCLUSION

Compared with high ligation, low ligation of the inferior mesenteric artery resulted in lower likelihood of morbidity and mortality in rectal and sigmoid cancers. Moreover, low ligation was less likely to result in anastomosis leakage in mid- to low-rectal cancers.

Risk factors for and longitudinal course of male sexual dysfunction after robotic rectal cancer surgery

AIM

The aim of this work was to investigate the risk factors associated with the incidence of sexual dysfunction in patients who underwent robot-assisted surgery with several treatment options, such as neoadjuvant chemoradiotherapy and lateral lymph node dissection, and clarify the longitudinal course of erectile function in risk groups.

METHOD

A total of 203 male patients who underwent robot-assisted total mesorectal excision for rectal cancer between 2013 and 2019 were included. The risk factors for erectile and ejaculatory dysfunction as well as the longitudinal course of erectile function were retrospectively investigated in all cohorts and several risk groups, including those who underwent neoadjuvant chemoradiotherapy, lateral lymph node dissection and adjuvant chemotherapy. Erectile dysfunction was assessed using the International Index of Erectile Function and ejaculatory dysfunction was assessed using original questions. The survey was performed preoperatively and at 3, 6 and 12 months postoperatively.

RESULTS

Erectile and ejaculatory dysfunction occurred in 46.8% and 15.7% of the patients, respectively. Multivariate analysis showed that neoadjuvant chemoradiotherapy was an independent risk factor for erectile dysfunction. Erectile function recovered longitudinally to the preoperative level overall, as well as in lateral lymph node dissection and postoperative adjuvant chemotherapy subgroups; however, recovery was poor in the neoadjuvant chemoradiotherapy group, even at 12 months postoperatively.

CONCLUSION

Neoadjuvant chemoradiotherapy was found to be a risk factor for erectile dysfunction after robot-assisted surgery for rectal cancer. Erectile function recovered postoperatively in patients undergoing lateral lymph node dissection; however, those receiving neoadjuvant chemoradiotherapy showed poor recovery, even at 12 months postoperatively.

High and low inferior mesenteric artery ligation in laparoscopic low anterior rectal resections: A retrospective study

Backgroud

The high or low inferior mesenteric artery (IMA) ligation in rectal cancer remains a great debate. This study retrospectively discussed the outcomes of the perioperative period, defecation and urinary function and long-term prognosis in rectal cancer patients with high or low IMA ligation.

Methods

This study enrolled 220 consecutive rectal cancer cases, including 134 with high IMA ligation and 86 with low ligation. A comparison between the two groups was made for anastomotic leakage, low anterior resection syndrome (LARS), international prostate symptom score (IPSS), 5-year disease-free survival (DFS) and 5-year overall survival (OS).

Results

Low-ligation group had a longer operative time, and larger intraoperative blood loss. No significant difference was noted in anastomotic leakage incidence. In multivariable analysis, the male gender and tumor located at the lower rectum were identified as risk factors for anastomotic leakage. No significant differences were observed between groups in their LARS and IPSS questionnaire responses. The high-ligation vs. the low-ligation 5-year OS and DFS were 78.3% vs. 82.4% and 72.4% vs. 76.6%, respectively, which were not statistically different.

Conclusion

The ligation level of the IMA had no significant effect on the anastomotic leakage incidence, defecation, urinary function, and long-term prognosis.

Impact of gastric and bowel surgery on gastrointestinal drug delivery

General surgical procedures on the gastrointestinal tract are commonly performed worldwide. Surgical resections of the stomach, small intestine, or large intestine can have a significant impact on the anatomy and physiological environment of the gastrointestinal tract. These physiological changes can affect the effectiveness of orally administered formulations and drug absorption and, therefore, should be considered in rational drug formulation design for specific pathological conditions that are commonly associated with surgical intervention. For optimal drug delivery, it is important to understand how different surgical procedures affect the short-term and long-term functionality of the gastrointestinal tract. The significance of the surgical intervention is dependent on factors such as the specific region of resection, the degree of the resection, the adaptive and absorptive capacity of the remaining tissue, and the nature of the underlying disease. This review will focus on the common pathological conditions affecting the gastric and bowel regions that may require surgical intervention and the physiological impact of the surgery on gastrointestinal drug delivery. The pharmaceutical considerations for conventional and novel oral drug delivery approaches that may be impacted by general surgical procedures of the gastrointestinal tract will also be addressed.

Selective approach to arterial ligation in radical sigmoid colon cancer surgery with D3 lymph node dissection: A multicenter comparative study

Objectives

Radical surgery for sigmoid colon cancer is commonly performed with complete mesocolic excision (CME) and apical lymph node dissection, reached by central vascular ligation (CVL) of the inferior mesenteric artery (IMA) and associated extended left colon resection. However, IMA branches can be ligated selectively according to tumor location with D3 lymph node dissection (LND), economic segmental colon resection and tumorspecific mesocolon excision (TSME) if IMA is skeletonized. This study aimed to compare left hemicolectomy with CME and CVL and segmental colon resection with selective vascular ligation (SVL) and D3 LND.

Material and Methods

Patients (n= 217) treated with D3 LND for adenocarcinoma of the sigmoid colon between January 2013 and January 2020 were included in the study. The approach to vessel ligation, colon resection and mesocolon excision was based on tumor location in the study group, while in the comparison group, left hemicolectomy with routine CVL was performed. Survival rates were estimated as the primary endpoints of the study. Long- and short-term surgery-related outcomes were evaluated as the secondary endpoints of the study.

Results

The studied approach to the IMA branch ligation was associated with a statistically significant decrease in intraoperative complication rates (2 vs 4, p= 0.024), operative procedure length (225.56 ± 80.356 vs 330.69 ± 175.488, p <0.001), and severe postoperative morbidity (6.2% vs 19.1%, p= 0.017). Meanwhile, the number of examined lymph nodes significantly increased (35.67 vs 26.69 per specimen, p <0.001). There were no statistically significant differences in survival rates.

Conclusion

Selective IMA branch ligation and TSME resulted in better intraoperative and postoperative outcomes with no difference in survival rates.

Development and validation of artificial intelligence models for preoperative prediction of inferior mesenteric artery lymph nodes metastasis in left colon and rectal cancer

BACKGROUND

Dissection of lymph nodes at the roots of the inferior mesenteric artery (IMAN) should be offered only to selected patients at a major risk of developing IMAN involvement. The aim of this study is to present the first artificial intelligence (AI) models to predict IMAN metastasis risk in the left colon and rectal cancer patients.

METHODS

A total of 2891 patients with descending colon including splenic flexure, sigmoid colon and rectal cancer undergoing major primary surgery and IMAN dissection were included as a study cohort, which was then split into a training set (67%) and a testing set (33%). Feature selection was conducted using the least absolute shrinkage and selection operator (LASSO) regression model. Seven AI algorithms, namely Support Vector Machine (SVM), Logistic Regression (LR), Extreme Gradient Boosting (XGB), Light Gradient Boosting (LGB), Decision Tree Classifier (DTC), Random Forest (RF) classifier, and Multilayer Perceptron (MLP), as well as traditional multivariate LR model were employed to construct predictive models. The optimal hyperparameters were determined with 5 fold cross-validation. The predictive performance of models and the expert surgeon was assessed and compared in the testing set independently.

RESULTS

The IMAN involvement incidence was 4.6%. The optimal set of features selected by LASSO included 10 characteristics: neoadjuvant treatment, age, synchronous liver metastasis, synchronous lung metastasis, signet ring adenocarcinoma, neural invasion, lymphovascular invasion, CA199, endoscopic obstruction, T stage evaluated by MRI. The most accurate model derived from MLP showed excellent prediction power with area under the receiver operating characteristic curve (AUROC) of 0.873 and produced 81.0% recognition sensitivity and 82.5% specificity in the testing set independently. In contrast, the judgment of IMAN metastasis by expert surgeon yield rather imprecise and unreliable results with a significantly lower AUROC of 0.509. Additionally, the proposed MLP had the highest net benefits and the largest reduction of unnecessary IMAN dissection without the cost of additional involved IMAN missed.

CONCLUSION

MLP model was able to maintain its prediction accuracy in the testing set better than other models and expert surgeons. Our MLP model could be used to help identify IMA nodal metastasis and to select candidates for individual IMAN dissection.

Comparison of high or modified low tie of the inferior mesenteric artery in laparoscopic rectal cancer surgery: A meta-analysis

OBJECTIVE

The purpose of this study was to perform a meta-analysis comparing the oncological, intraoperative and safety outcomes in laparoscopic rectal cancer surgery with and without preservation of the left colic artery (LCA).

METHOD

We searched several databases including PubMed, Web of Science, Cochrane Library, and Embase databases. This meta-analysis included randomized clinical trials, prospective, and retrospective comparative studies regarding high- or modified low-tie ligation of the inferior mesenteric artery in laparoscopic rectal cancer surgery.

RESULTS

Of 641 potentially eligible articles, 16 studies with 3050 participants met the eligibility criteria and were included in the meta-analysis. There was no significant difference in estimated blood loss (WMD -2.63, 95% CI -5.69 to 0.43; P = .09), the number of harvested lymph nodes (WMD -0.35, 95% CI -1.60 to 0.20; P = .50), the number of apical lymph node yield (WMD -0.19, 95% CI -0.52 to 0.13; P = .24), the number of apical lymph node metastasis (OR 0.76, 95% CI 0.40 to 1.45; P = .40), rate of conversion to open surgery (OR 0.74, 95% CI 0.50 to 1.09; P = .513), rate of urinary dysfunction (OR 1.39, 95% CI 0.71 to 2.74; P = .34), rate of recurrence and metastasis (OR 1.10, 95% CI 0.75 to 1.61; P = .64), 5-year survival rate (OR 0.89, 95% CI 0.67 to 1.18; P = .42). However, this meta-analysis demonstrated a statistically significant difference in operating time (WMD -9.92, 95% CI -15.49 to -5.84; P = .0005), rate of diverting stom (OR 1.42, 95% CI 1.06 to 1.92; P = .02), rate of anastomotic leakage (OR 2.673, 95% CI 1.91 to 3.62; P < .00001), time to first flatus (WMD 0.29, 95% CI 0.11 to 0.48; P = .002), time of hospitalization (WMD 0.64, 95% CI 0.14 to 1.15; P = .01) between the 2 surgical techniques.

COCLUSION

The available evidence suggests that preserving the left colic artery is a safe, effective technique for patients with laparoscopic rectal cancer. nique for patients with laparoscopic rectal cancer.

Anastomotic leak after minimally invasive anterior resection for rectal cancer with high versus low ligation of the inferior mesenteric artery: a study protocol for a multicentre randomized clinical trial

BACKGROUND

Although many efforts have been made to decrease the incidence of anastomotic leak (AL), it remains one of the most serious complications of rectal cancer surgery. Many previous studies have reported an association between the ligation level of the inferior mesenteric artery (IMA) (high or low) and the incidence of AL after rectal cancer surgery. However, we cannot draw a solid conclusion because of the low quality and heterogeneity of those studies. Therefore, this study aims to investigate the impact of the IMA ligation level on the occurrence of AL after minimally invasive anterior resection of rectal cancer.

METHODS/DESIGN

Patients with primary rectal cancer without distant metastases will be included after screening. They will be randomly assigned (1:1) to receive high or low ligation of the IMA. The primary endpoint is AL incidence; secondary endpoints are quality of life; urinary, sexual, and defecatory functions; and 3-year disease-free survival. We hypothesized that the incidence rate of AL would be 15% and 5% in the high- and low-ligation groups, respectively. With a two-sided α of 0.05 and a power of 0.8, the sample size is calculated to be 314 patients (157 per group), considering a 10% dropout rate.

DISCUSSION

Although many studies have compared the short- and long-term outcomes of high and low ligation of the IMA in rectal cancer surgery, it is still debatable. This trial aims to help draw a more solid conclusion regarding the association between the IMA ligation level and AL incidence after rectal cancer surgery. We also hope to contribute to standardizing the method of rectal cancer surgery in this trial.

TRIAL REGISTRATION

Clinical Research Information Service KCT0003523. Registered on February 18, 2019.

Does the level of inferior mesenteric artery ligation affect short-term and long-term outcomes of patients with sigmoid colon cancer or rectal cancer? A single-center retrospective study

Background

For sigmoid colon or rectal cancer, a definite consensus regarding the optimal level ligating the inferior mesenteric artery (IMA) has not been reached. We performed this study to determine whether the ligation level significantly affected short-term and long-term outcomes of patients with sigmoid colon or rectal cancer after curative laparoscopic surgery.

Methods

Medical records of patients with sigmoid colon or rectal cancer who had undergone curative laparoscopic surgery between January 2008 and December 2014 at the Department of Gastrointestinal Surgery, Guangdong Provincial Hospital of Traditional Chinese Medicine were reviewed. Then, the high tie group (HTG) was compared with the low tie group (LTG) in terms of short-term and long-term outcomes.

Results

Five-hundred ninety patients were included. No significant differences between two groups regarding baseline characteristics existed. HTG had a significantly higher risk of anastomotic fistula than LTG (21/283 vs 11/307, P = 0.040). Additionally, high ligation was proven by multivariate logistic regression analysis to be an independent factor for anastomotic fistula (P = 0.038, OR = 2.232, 95% CI: 1.047–4.758). Furthermore, LT resulted in better preserved urinary function. However, LTG was not significantly different from HTG regarding operative time (P = 0.075), blood transfusion (P = 1.000), estimated blood loss (P = 0.239), 30-day mortality (P = 1.000), ICU stay (P = 0.674), postoperative hospital stay (days) (P = 0.636), bowel obstruction (P = 0.659), ileus (P = 0.637), surgical site infection (SSI) (P = 0.121), number of retrieved lymph nodes (P = 0.501), and number of metastatic lymph nodes (P = 0.131). Subsequently, it was revealed that level of IMA ligation did not significantly influence overall survival (OS) (P = 0.474) and relapse-free survival (RFS) (P = 0.722). Additionally, it was revealed that ligation level did not significantly affect OS (P = 0.460) and RFS (P = 0.979) of patients with stage 1 cancer, which was also observed among patients with stage 2 or stage 3 cancer. Ultimately, ligation level was not an independent predictive factor for either OS or RFS.

Conclusions

HT resulted in a significantly higher incidence of anastomotic fistula and worse preservation of urinary function. Level of IMA ligation did not significantly affect long-term outcomes of patients with sigmoid colon or rectal cancer after curative laparoscopic surgery.

Clinical impact of inferior mesenteric vein preservation during left hemicolectomy with low ligation of the inferior mesenteric artery for distal transverse and descending colon cancers: A comparative study based on computed tomography

Purpose

Presence of a long remnant sigmoid colon after left hemicolectomy with inferior mesenteric vein (IMV) ligation for distal transverse and descending colon cancers may be a risk factor for venous ischemia. This study aimed to evaluate the clinical impact of IMV preservation in patients who underwent left hemicolectomy with inferior mesenteric artery (IMA) preservation.

Methods

We included 155 patients who underwent left hemicolectomy with IMA preservation for distal transverse and descending colon cancers from 2003 to 2020. Technical success of IMV preservation was determined by assessing pre- and post-operative patency of the IMV on computed tomography (CT) by an abdominal radiologist. Intestinal complications comprising ulceration, stricture, venous engorgement, and colitis in remnant colon were compared between the IMV preservation and ligation groups.

Results

IMV was preserved in 22 (14.2%) and ligated in 133 (85.8%) patients. Surgical time, postoperative recovery outcomes, and number of harvested lymph nodes were similar in both groups. The technical success of IMV preservation was 81.8%. Intestinal complications were less common in the preservation group than in the IMV ligation group (4.5% vs. 23.3%, P=0.048). The complications in the IMV ligation group were anastomotic ulcer (n=2), anastomotic stricture (n=4), venous engorgement of the remnant distal colon (n=4), and colitis in the distal colon (n=21).

Conclusions

IMV preservation may be beneficial after left hemicolectomy with IMA preservation for distal transverse and descending colon cancers. We suggest that IMV preservation might be considered when long remnant sigmoid colon is expected during left hemicolectomy with low ligation of IMA.

High Versus Low Ligation of the Inferior Mesenteric Artery in Colorectal Cancer Surgery: A Systematic Review and Meta-Analysis

Background and Objectives: This study aimed to compare the effects of high ligation (HL) versus low ligation (LL) in colorectal cancer surgery. Materials and Methods: We performed a comprehensive search using multiple databases (trial registries and ClinicalTrials.gov), other sources of grey literature, and conference proceedings, with no restrictions on the language or publication status, up until 10 March 2021. We included all parallel-group randomized controlled trials (RCTs) and considered cluster RCTs for inclusion. The risk of bias domains were "low risk," "high risk," or "unclear risk." We performed statistical analyses using a random-effects model and interpreted the results according to the Cochrane Handbook for Systematic Reviews of Interventions. We used the GRADE guidelines to rate the certainty of evidence (CoE) of the randomized controlled trials. Results: We found 12 studies (24 articles) from our search. We were very uncertain about the effects of HL on overall mortality, disease recurrence, cancer-specific mortality, postoperative mortality, and anastomotic leakage (very low CoE). There may be little to no difference between HL and LL in postoperative complications (low CoE). For short-term follow-up (within 6 months), HL may reduce defecatory function (constipation; low CoE). While HL and LL may have similar effects on sexual function in men, HL may reduce female sexual function compared with LL (low CoE). For long-term follow-up (beyond 6 months), HL may reduce defecatory function (constipation; low CoE). There were discrepancies in the effects regarding urinary dysfunction according to which questionnaire was used in the studies. HL may reduce male and female sexual function (low CoE). Conclusions: We are very uncertain about the effects of HL on survival outcomes, and there is no difference in the incidence of postoperative complications between HL and LL. More rigorous RCTs are necessary to evaluate the effect of HL and LL on functional outcomes.

Lymph Node Cluster Dissection After Carbon Nanoparticles Injection Enhances the Retrieval Number in Colorectal Cancer

For colorectal cancer patients, NCCN recommended that at least 12 lymph nodes should be detected since the number and metastases status of lymph nodes played an important role in the treatment and prognostic. Carbon nanoparticles have been proved to be an efficient lymph node tracer. Faced with the clinical problem of insufficient lymph nodes in colorectal cancer, we proposed a lymph node cluster (D3, D2 and D1) dissection method combined with carbon nanoparticle injection. In our study, patients were divided into 2 groups (CNP and control). All lymph nodes of each patient were collected and made into hematoxylin-eosin sections to observe their size, staining appearance and metastasis status under the microscope. As a result, the total lymph nodes in CNP group were greatly higher than control group (51.45 vs. 29.62, P = 0.000), especially micro LNs and positive micro LNs. Compared with D2 and D1 stations, fewer lymph nodes were found in D3, and it was the same for cancer metastasis status. In CNP group, most lymph nodes got black for quick visualization. In conclusion, lymph node cluster dissection combined with carbon nanoparticles could enhance the number of lymph node retrieval.

Systematic review and meta-analysis of randomized controlled trials evaluating the effect of the level of ligation of inferior mesenteric artery on functional outcomes in rectal cancer surgery

BACKGROUND

This systematic review and meta-analysis studied the role of high (HL) versus low (LL) inferior mesenteric artery (IMA) ligation on genitourinary and defecatory dysfunction in patients who had undergone resection for rectal cancer (RC).

METHODS

A systematic literature search of four major databases was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Randomized controlled trials (RCTs) comparing HL and LL of IMA in RC surgery were identified. Those studies that looked at genitourinary or defecatory dysfunction were included. Random-effects modeling to summarize statistics was performed. The risk of bias was assessed using Cochrane's Risk-of-Bias tool 2.

RESULTS

Three RCTs were included. There was clinical heterogeneity with regard to cancer stage and location as well as operative techniques and adjuvant treatments. Functional outcomes (FO) that were reported by at least two studies were International Consultation on Incontinence Questionnaire (ICIQ), International Index for Erectile Function (IIEF), Jorge-Wexner incontinence score (J-W). Difference was observed in ICIQ at 9 months after surgery favoring LL (standard mean difference: - 0.66; 95% confidence intervals (CI): - 0.92, - 0.40; P = 0.37; I 2 = 0%). Difference was also observed in IIEF at 9 months favoring LL (mean difference: 7.43; CI: 1.86, 13.00; P = 0.16; I 2 = 50%).

CONCLUSIONS

Although our study has demonstrated the superiority of LL in genitourinary function preservation, these results should be taken with consciousness due to significant heterogeneity between included studies, small sample size, and potential bias. More high-quality studies are needed.

PROSPERO

CRD4202121099  https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021210998.

Extended Versus Standard Complete Mesocolon Excision in Sigmoid Colon Cancer: A Multicenter Randomized Controlled Trial

OBJECTIVE

The aim of this study was to evaluate whether extended complete mesocolic excision (e-CME) for sigmoid colon cancer improves oncological outcomes without compromising morbidity or functional results.

BACKGROUND

In surgery for cancer of the sigmoid colon and upper rectum, s-CME removes the lymphofatty tissue surrounding the inferior mesenteric artery (IMA), but not the lymphofatty tissue surrounding the portion of the inferior mesenteric vein that does not run parallel to the IMA. Evidence about the safety and efficacy of extending CME to include this tissue is lacking.

METHODS

This single-blind study randomized sigmoid cancer patients at 4 centers to undergo e-CME or s-CME. The primary outcome was the total number of lymph nodes harvested. Secondary outcomes included disease-free and overall survival at 2 years, morbidity, and bowel and genitourinary function. Clinicaltrials.gov: NCT03107650.

RESULTS

We analyzed 93 patients (46 e-CME and 47 s-CME). Perioperative outcomes were similar between groups. No differences between groups were found in the total number of lymph nodes harvested [21 (interquartile range, IQR, 14-29) in e-CME vs 20 (IQR, 15-27) in s-CME, P = 0.873], morbidity (P = 0.829), disease-free survival (P = 0.926), or overall survival (P = 0.564). The extended specimen yielded a median of 1 lymph node (range, 0-6), none of which were positive.Bowel function recovery was similar between arms at all timepoints. Males undergoing e-CME had worse recovery of urinary function (P = 0.026).

CONCLUSION

Extending lymphadenectomy to include the IMV territory did not increase the number of lymph nodes or improve local recurrence or survival rates.

Prognosis of Patients With Colorectal Cancer and Apical Lymph Node Metastasis at the Inferior Mesenteric Artery: A Systematic Review and Meta-Analysis

Background

This review was designed to compile the evidence on the prognosis of patients with colorectal cancer and apical lymph node (APN) metastasis and the long-term benefit of inferior mesenteric artery lymph node (IMA-LN) resection.

Methods

We searched the PubMed Central, Cochrane library, EMBASE, and MEDLINE databases from inception until May 2021 for relevant publications. We assess the quality of the studies using the Newcastle Ottawa scale. We conducted a random-effects model meta-analysis and report pooled hazard ratios (HRs) with 95% confidence intervals (CIs).

Results

We analyzed data from 13 studies conducted in Japan, China, and Korea with 6,193 participants. Most studies were retrospective in nature and of low quality. We found that patients with APN metastasis had shorter OSs (pooled HR, 2.41; 95% CI, 1.92–3.02) and PFSs (pooled HR, 2.42; 95% CI, 1.90–3.09) than the patients without the metastasis. We identified significant heterogeneity without publication bias for both outcomes. Moreover, our sensitivity analysis revealed robust estimates were robust for the individual effects.

Conclusion

Our findings suggest that patients with colorectal cancer and APN metastases have significantly worse OS and DFS than those without the metastasis. However, inclusion of low-quality retrospective studies with high heterogeneity limits the generalizability of study findings.

Surgeon's role in CT-based preoperative determination of inferior mesenteric artery anatomy in colorectal cancer treatment

BACKGROUND

The inferior mesenteric artery (IMA) is a blood vessel of great importance in left colon and rectal cancer surgery. We aimed to determine the role of surgeons in computed tomography (CT) based vascular anatomy interpretation.

METHOD

Patients with left colon and rectal cancer treated surgically with D3 lymph node dissection and selective vascular ligation were included in this study. All patients (n=250) underwent preoperative CT with intravenous contrast. The IMA anatomy was schematically depicted by surgeon based on CT interpretation. Intraoperatively anatomy was defined by skeletonisation of the IMA. All patients had segmental resection with selective vascular ligation. The concurrence of prospectively obtained results were evaluated by intraclass correlation and Kendall's tau-b test. Misinterpretation of IMA anatomy was analysed by CT-specialist.

RESULTS

The preoperative and intraoperative IMA anatomy features were correctly interpreted in 237 cases (in 94.8%) within skeletonisation extent, which is supported by high level of agreement and concordance of preoperative data regards to intraoperative findings (K=0.926; p<0.001; CC=0.912; p<0.001). As a result of the CT-based evaluation of the IMA, E, K, and H types of branching patterns were proposed. IMV position was mistakenly identified in 2.6% of cases.

CONCLUSION

Surgeons are able to evaluate the IMA anatomy accurately with CT and use it in routine preoperative planning. The E, K, and H branching types may be used when defining approach to skeletonisation and level of vascular ligation.

Prognostic Value of the Distribution of Lymph Node Metastasis in Locally Advanced Rectal Cancer After Neoadjuvant Chemoradiotherapy

Background: The objective of this study is to assess the prognostic value of lymph node metastasis distribution (LND) in locally advanced rectal cancer (LARC) after neoadjuvant chemoradiotherapy (nCRT). Methods: This study included 179 patients with pathological stage III LARC who underwent nCRT followed by radical surgery. LND was classified into three groups: LND1, lymph node metastasis at the mesorectum (140/179, 78.2%); LND2, lymph node metastasis along the inferior mesenteric artery trunk nodes (26/179, 14.5%); LND3, lymph node metastasis at the origin of the IMA (13/179, 7.3%). Clinicopathologic characteristics were analyzed to identify independent prognostic factors. Result: LND showed better stratification for 3-year DFS (LND1 66.8, LND2 50, and LND3 15.4%, P < 0.01) compared to the ypN (3-year DFS: N1 59.9 and N2 60.3%, P = 0.34) and ypTNM (3-year DFS: IIIA 68.6%, IIIB 57.5%, and IIIC 53.5, P = 0.19) staging systems. Similar results were found for 3-year LRFS and DMFS. According to multivariate survival analysis, LND was shown to be an independent prognostic factor for DFS, LRFS, and DMFS in patients with positive lymph nodes (P < 0.01, in all cases). Conclusion: LND is an independent prognostic factor in stage III rectal cancer after nCRT. LND can be used as a supplementary indicator for the ypTNM staging system in patients with LARC after nCRT.

Low Ligation Plus High Dissection Versus High Ligation of the Inferior Mesenteric Artery in Sigmoid Colon and Rectal Cancer Surgery: A Meta-Analysis

Background

Whether high or low ligation of the inferior mesenteric artery (IMA) is superior in surgery for rectal and sigmoid colon cancers remains controversial. Although several meta-analyses have been conducted, the level of lymph node clearance was poorly defined. We performed a meta-analysis comparing high and low ligation of the IMA for sigmoid colon and rectal cancers, with emphasis on high dissection of the lymph node at the IMA root in all the included studies.

Methods

PubMed, MEDLINE, and EMBASE databases were searched to identify relevant articles published until 2020. The patient’s perioperative and oncologic outcomes were analyzed. Statistical analysis was performed using the statistical software RevMan version 5.4.

Results

A total of 17 studies, including four randomized controlled trials, published between 2011 and 2020 were selected. In total, 1,846 patients received low ligation of the IMA plus high dissection of lymph nodes (LL+HD), and 2,648 patients received high ligation of the IMA (HL). LL+HD was associated with low incidence of anastomotic leakage (p < 0.001), borderline long operative time (p = 0.06), and less yields of total lymph nodes (p = 0.03) but equivalent IMA root lymph nodes (p = 0.07); moreover, LL+HD exhibited non-inferior long-term oncological outcomes.

Conclusion

In comparison with HL, LL+HD was an effective and safe oncological procedure for sigmoid colon and rectal cancers. Therefore, to ligate the IMA below the level of the left colic artery with D3 high dissection for sigmoid colon and rectal cancers might be suggested once the surgeons are familiar with this technique.

Systematic Review Registration

INPLASY.com, identifier 202190029.

A US Rectal Cancer Consortium Study of Inferior Mesenteric Artery Versus Superior Rectal Artery Ligation: How High Do We Need to Go?

BACKGROUND

The optimal level of pedicle ligation during proctectomy for rectal cancer, either at the origin of the inferior mesenteric artery or the superior rectal artery, is still debated.

OBJECTIVE

The objective was to determine whether superior rectal artery ligation portends equivalent technical or oncologic outcomes.

DESIGN

This was a retrospective analysis of a rectal cancer database (2007-2017).

SETTINGS

The study was conducted at 6 tertiary referral centers in the United States (Emory University, University of Michigan, University of Pittsburgh Medical Center, The Ohio State University Wexner Medical Center, Vanderbilt University Medical Center, and Washington University School of Medicine in St. Louis).

PATIENTS

Patients with primary, nonmetastatic rectal cancer who underwent low anterior resection or abdominoperineal resection were included.

MAIN OUTCOME MEASURES

Anastomotic leak, lymph node harvest, locoregional recurrence-free survival, recurrence-free survival, and overall survival were measured.

RESULTS

Of 877 patients, 86% (n = 755) received an inferior mesenteric artery ligation, whereas 14% (n = 122) received a superior rectal artery ligation. A total of 12%, 33%, 24%, and 31% were pathologic stage 0, I, II, and III. Median follow-up was 31 months. Superior rectal artery ligation was associated with a similar anastomotic leak rate compared with inferior mesenteric artery ligation (9% vs 8%; p = 1.0). The median number of lymph nodes removed was identical (15 vs 15; p = 0.38). On multivariable analysis accounting for relevant clinicopathologic factors, superior rectal artery ligation was not associated with increased anastomotic leak rate, worse lymph node harvest, or worse locoregional recurrence-free survival, recurrence-free survival, or overall survival (all p values >0.1).

LIMITATIONS

This was a retrospective design.

CONCLUSIONS

Compared with inferior mesenteric artery ligation, superior rectal artery ligation is not associated with either worse technical or oncologic outcomes. Given the potential risks of inadequate blood flow to the proximal limb of the anastomosis and autonomic nerve injury, we advocate for increased use of superior rectal artery ligation. See Video Abstract at http://links.lww.com/DCR/B646.

ESTUDIO DEL CONSORCIO DE CNCER DE RECTO DE ESTADOS UNIDOS DE LIGADURA BAJA DE LA ARTERIA MESENTRICA INFERIOR CONTRA LIGADURA ALTA DE LA ARTERIA MESENTRICA INFERIOR QU TAN ALTO DEBEMOS EXTENDERNOS

ANTECEDENTES:el nivel óptimo de la ligadura del pedículo en la proctectomía para el cáncer de recto, ya sea en el origen de la arteria mesentérica inferior o en la arteria rectal superior aún no esta definido.OBJETIVO:El objetivo era determinar si la ligadura de la arteria rectal superior pronostica resultados técnicos u oncológicos similares.DISEÑO:Análisis retrospectivo de una base de datos de cáncer de recto (2007-2017).ESCENARIO:el estudio se realizó en seis centros de referencia de tercer nivel en los Estados Unidos (Universidad de Emory, Universidad de Michigan, Centro médico de la Universidad de Pittsburgh, Centro médico Wexner de la Universidad Estatal de Ohio, Centro médico de la Universidad de Vanderbilt y Escuela de Medicina de la Universidad de Washington en St. Louis).PACIENTES:Se incluyeron pacientes con cáncer de recto primario no metastásico que se sometieron a resección anterior baja o resección abdominoperineal.PRINCIPALES VARIABLES ANALIZADAS:Se midió la fuga anastomótica, los ganglios linfáticos recuperados, la sobrevida sin recidiva locorregional, la sobrevida sin recidiva y la sobrevida global.RESULTADOS:De 877 pacientes, en el 86% (n = 755) se realizó una ligadura de la arteria mesentérica inferior, y en el 14% (n = 122) se realizó una ligadura de la arteria rectal superior. El 12%, 33%, 24% y 31% estaban en estadio patológico 0, I, II y III respectivamente. La mediana de seguimiento fue de 31 meses. La ligadura de la arteria rectal superior se asoció con una tasa de fuga anastomótica similar a la ligadura de la arteria mesentérica inferior (9 vs 8%, p = 1,0). La mediana del número de ganglios linfáticos extirpados fue idéntica (15 contra 15, p = 0,38). En el análisis multivariado que tiene en cuenta los factores clínico-patológicos relevantes, la ligadura de la arteria rectal superior no se asoció con una mayor tasa de fuga anastomótica, una peor cosecha de ganglios linfáticos o una peor sobrevida libre de recurrencia locorregional, sobrevida libre de recurrencia o sobrevida global (todos p> 0,1).LIMITACIONES:Diseño retrospectivo.CONCLUSIONES:En comparación con la ligadura de la arteria mesentérica inferior, la ligadura de la arteria rectal superior no se asocia a peores resultados técnicos ni oncológicos. Debido a los riesgos potenciales de un flujo sanguíneo inadecuado del muñon proximal de la anastomosis y la lesión de los nervios autonómicos, proponemos una mayor realización de la ligadura de la arteria rectal superior. Consulte Video Resumen en http://links.lww.com/DCR/B646.

Level of inferior mesenteric artery ligation does not affect rectal cancer treatment outcomes despite better cancer-specific survival after low ligation-randomized trial results

AIM

In rectal cancer surgery, the problem about which of the mesenteric artery ligation variants (high or low) is more beneficial to the patient remains unsolved. Recent meta-analyses suggest that the risk of surgical complications is similar for both ligation variants. The main objective was to compare the survival time in both groups with a minimum 48 months' follow-up. Secondary objectives were comparison of the number of harvested lymph nodes, the complication rate and other selected data related to the surgery.

METHOD

This was a randomized, single-centre, unblinded clinical trial of adult patients (n = 130) with cT1-3M0/ycT0-3M0 rectal and rectosigmoid junction adenocarcinoma undergoing radical open surgery. The intervention level was inferior mesenteric artery ligation.

RESULTS

The mean and median survival in the whole group was 45 months, while in the survivor group it was 83 and 82 months. The survival for 1-5 years, overall survival and disease-free survival were similar in both groups. The cancer-specific survival time was longer in the low inferior mesenteric artery ligation group (P = 0.005 for all and P = 0.02 for pTNM Stage III patients) There were no differences in the incidence of anastomotic leakage and overall morbidity. The median number of lymph nodes located at the root of the inferior mesenteric artery was 1; the mean was 1.7. They were not metastatic in any case. The median total number of harvested nodes was similar in both groups.

CONCLUSIONS

In radically treated adenocarcinoma of the rectum and the rectosigmoid junction, the level of inferior mesenteric artery ligation below the left colic artery branch provides similar treatment results to inferior mesenteric artery ligation just below its branching from the aorta in relation to overall and disease-free survival, and the risk of complications. Low inferior mesenteric artery ligation results in better cancer-specific survival. The risk of metastases at the mesenteric nodes is negligible.

Genitourinary function and defecation after colorectal cancer surgery with low- and high-ligation of the inferior mesenteric artery: A meta-analysis

BACKGROUND

The effect of low ligation (LL) vs high ligation (HL) of the inferior mesenteric artery (IMA) on functional outcomes during sigmoid colon and rectal cancer surgery, including urinary, sexual, and bowel function, is still controversial.

AIM

To assess the effect of LL of the IMA on genitourinary function and defecation after colorectal cancer (CRC) surgery.

METHODS

EMBASE, PubMed, Web of Science, and the Cochrane Library were systematically searched to retrieve studies describing sigmoid colon and rectal cancer surgery in order to compare outcomes following LL and HL. A total of 14 articles, including 4750 patients, were analyzed using Review Manager 5.3 software. Dichotomous results are expressed as odds ratios (ORs) with 95% confidence intervals (CIs) and continuous outcomes are expressed as weighted mean differences (WMDs) with 95%CIs.

RESULTS

LL resulted in a significantly lower incidence of nocturnal bowel movement (OR = 0.73, 95%CI: 0.55 to 0.97, P = 0.03) and anastomotic stenosis (OR = 0.31, 95%CI: 0.16 to 0.62, P = 0.0009) compared with HL. The risk of postoperative urinary dysfunction, however, did not differ significantly between the two techniques. The meta-analysis also showed no significant differences between LL and HL in terms of anastomotic leakage, postoperative complications, total lymph nodes harvested, blood loss, operation time, tumor recurrence, mortality, 5-year overall survival rate, or 5-year disease-free survival rate.

CONCLUSION

Since LL may result in better bowel function and a reduced rate of anastomotic stenosis following CRC surgeries, we suggest that LL be preferred over HL.

Quantitative evaluation of colon perfusion after high versus low ligation in rectal surgery by indocyanine green: a pilot study

BACKGROUND

In the field of rectal cancer surgery, there remains ongoing debate on the merits of high ligation (HL) and low ligation (LL) of the inferior mesenteric artery (IMA) in terms of perfusion and anastomosis leakage. Recently, infrared fluorescence of indocyanine green (ICG) imaging has been used to evaluate perfusion status during colorectal surgery.

OBJECTIVE

The purpose of this study is to compare the changes in perfusion status between HL and LL through quantitative evaluation of ICG.

METHODS

Patients with rectosigmoid or rectal cancer were randomized into a high or LL group. ICG was injected before and after IMA ligation, and region of interest (ROI) values were measured by an image analysis program (HSL video©).

RESULTS

From February to July 2020, 22 patients were enrolled, and 11 patients were assigned to each group. Basic demographics were similar between the two groups, except for albumin level and cardiac ejection fraction. There were no significant differences in F_max between the two groups, but T_max was significantly higher and Slope_max was significantly lower in the HL group than in the LL group. Anastomosis leakage was significantly associated with neoadjuvant chemoradiation and F_max.

CONCLUSION

After IMA ligation, T_max increased and Slope_max decreased significantly in the HL group. However, the intensity of perfusion status (F_max) did not change according to the level of IMA ligation.

Outcomes of level of ligation of inferior mesenteric artery in colorectal cancer: a systematic review and meta-analysis

The level of ligation of the inferior mesenteric artery (IMA) is a critical factor that can influence outcomes. The aim of this meta-analysis was to compare outcomes following high or low ligation of IMA. A systematic search was performed for relevant articles published between 2000 and 2020. Meta-analysis was performed using fixed-effects or random-effects models; 31 studies were included. Results show significantly lower rates of anastomotic leak, postoperative morbidity and urinary dysfunction with low ligation compared with high ligation. Though recurrence rates were similar, 5-year overall survival was longer in the low ligation group. Low ligation of IMA decreases anastomotic leak rates and overall morbidity. Addition of IMA nodal clearance to low ligation appears to improve overall survival in colorectal cancer.

An Intrasheath Separation Technique for Nerve-Sparing High Ligation of the Inferior Mesenteric Artery in Colorectal Cancer Surgery

Purpose

To investigate the relationship between the left trunk of the inferior mesenteric plexus (IMP) and the vascular sheath of the inferior mesenteric artery (IMA) and to explore anatomical evidence for autonomic nerve preservation during high ligation of the IMA in colorectal cancer surgery.

Methods

We evaluated the relationship in 23 consecutive cases of laparoscopic or robotic colorectal surgery with high ligation of the IMA at our institute. Anatomical dissection was performed on 5 formalin-fixed abdominal specimens. A novel anatomical evidence-based operative technique was proposed.

Results

Anatomical observation showed that the left trunk of the IMP was closely connected with the IMA and was involved in the composition of the vascular sheath. Based on anatomical evidence, we present a novel operative technique for nerve-sparing high ligation of the IMA that was successfully performed in 45 colorectal cancer surgeries with no intraoperative complications and satisfactory postoperative urogenital functional outcomes.

Conclusion

The left trunk of the IMP is involved in the composition of the IMA vascular sheath. This novel anatomical evidence-based operative technique for nerve-sparing high ligation of the IMA is technically safe and feasible.

Apical lymphadenectomy during low ligation of the IMA during rectosigmoid resection for cancer

Background

Low ligation of the inferior mesenteric artery with preservation of the left colic artery may decrease the risk of colorectal anastomotic ischemia compared to high ligation at its origin. Low ligation leaves apical nodes in situ and is therefore paired with apical lymphadenectomy. We sought to compare relevant oncologic outcomes between high ligation and low ligation plus apical lymphadenectomy in rectosigmoid resection for colorectal cancer.

Methods

We conducted a retrospective cohort study. Patients receiving a rectosigmoid resection for cancer between January 2012 and July 2018 were included. Patients with metastatic disease and those who underwent low ligation without apical lymphadenectomy were excluded. Our primary outcome was nodal yield/metastasis. Secondary outcomes included perioperative complications, local recurrence, and overall survival.

Results

Eighty-four patients underwent high ligation and 89 low ligation plus apical lymphadenectomy (median follow-up 20 months). In the low-ligation group, a median of 2 (interquartile range = 1–3) apical nodes was resected; 4.1% were malignant, increasing pathologic stage in 25% of these patients. There were no differences in nodal yield, complications, anastomotic leak, local recurrence, or overall survival.

Conclusion

No differences were identified between high ligation and low ligation plus apical lymphadenectomy with respect to relevant clinical outcomes. Prospective trial data are needed to robustly establish the oncologic benefit and safety of the low ligation plus apical lymphadenectomy technique.